Of the 122 students who took a mathematics exam, 76 correctly answered the first question, 60 correctly answered the second question, and 38 correctly answered both questions. how many students answered the first question correctly, but not the second? students answered the first question correctly, but not the second

38

Step-by-step explanation:

                 i.e.

Let A be the number of students who correctly answered the first question and B be the number of students who correctly answered the second question .

Given :

Then the number of students who answered the first question correctly, but not the second is given by :-

Hence, the number of students who answered the first question correctly, but not the second is 38.

i dont have an answer

step-by-step explanation:

hello!

to begin with, we're given that on earth, a rock weighs 20 pounds, and while on jupiter, that same rock weighs 42 pounds. now, we're trying to find the weight of a rock that weighs 10.5 pounds on earth, on jupiter.

to solve this, first, set up a proportion, cross-multiply, and solve it algebraically.

setting up the proportion is the hardest and the most confusing part of the problem, but it's simple.

if on earth, the rock weighs 20 lbs, and on jupiter it weighs 42 lbs, our first part of our proportion is 20/42 lbs. the second part has to be equal to each other. this means that 10.5 has to be on the numerator of the fraction, and x, the value we're trying to find, has to be on the denominator. remember that the rock weighs 10.5 lbs on earth, and we're trying to find the weight of it on jupiter (which is x).

20/42 = 10.5/x

next, you would cross-multiply.

20x = 42(10.5)

20x = 441

now, solve it algebraically by using division.

x = 22.05 lbs

this can be rounded to 22.1 lbs.

therefore, the weight of the rock on jupiter is 22.1 lbs, the fourth choice.